This may seem impossible but during a global warming event about 56 million years ago there was a huge release of carbon into the atmosphere and the oceans raised the average global temperature 10 degrees over the course of 175,000 years.

Mammals reacted to this increase in heat by shrinking in size generation after generation.

The earliest-known horse, Sifrihippus was a 12 pound little thing, about the size of a miniature schnauzer.

By the end of this period of extreme global warming the Sifrihippus had shrunk down to about 8.5 pounds and was about the size of a house cat.

A researcher said:

"This, for the first time, tells us that temperature is what's driving the body size evolution for these horses."

So many animals get smaller and evolve to cope with global warming. The problem is that the same amount of warming that happened over the course of 175,000 years could happen to us within a century or so!!

"While our study provides a measure of possible response to global warming — that is, getting smaller — in a sense that is the best-case scenario."

He continued to say that if animals can't evolve quickly enough (which would be very hard to do in only 100 or so years) they will most likely go extinct.